Station Circular 68
February, 1926
Oregon Agricultural College
Experiment Station
Sprays, Their Mixing and the Compatibility of Various Combinations
By
CORVALLIS, OREGON
The regular bulletins of the Station are sent free to the residents of Oregon
who request them.
BOARD OF REGENTS OF THE OREGON AGRICULTURAL
COLLEGE AND EXPERIMENT STATION
HON. j. K, VEATiicaroRD, President........._............._...__........_.._...........klbany
Corvallis
Hos. E. F. Witsoa,
_.._.._ Portland
lbs. B. F. Iuvisr, 'lreasurcr...
.__.........
........Salem
Hog. WALTER M. PIERCE, Governor
Salem
Hos. Sat A. Kozvs, Srcrrtary of State
........Salem
Hofl. J. A. ChURCHILL, Superintendent of Public lnstruction.._..................
......Hood River
Hog. GEORGE A. PALMITER, Master of State Grange.........._...._.
........................ .......... ........Astoria
I-boa. Ms.. WI. S. Ktscv
Gervais
Lakeview
HON. SAM H. BROWN
HON. HARRY BAILEY
HON. GEO. M. CORNWALL
HON. E. B. ALDRiCH
Portland
Pendleton
Portland
HON. JEFFERSON MYERS
STATION STAFF
.....................President
W. J. KERR, D.Sc., LL.D
or
J. T. JARDINE, B.S
..................l)irect
Edit or
E. T. REED, B.S., A.B
........._....Plant Pathologist
I-b. P. lts.sss, A.11., S.M.
F. B. BAILEY, M.S..Jtsst. l'athologist, Insecticide and Fungicide Ud., U. S. i)ept. of Agri.
.....Jumor Agronomist, Office of Cer. inves., U. S. Dept. ot Agri.
B. B. BAY 1.ES
kssociate in Farm Management
K. S. Bgsss, M.S......
I'. M. BRAND; B.S., A.M
............. ............._.. ...._Dairy Husliandman
..........Horticulturist (Vegetable Gardening)
A. G. BoUQUET, B.S...............
.._.
Associate Agronomist
E. N. IIREASMAN, B.S
.... ..
Horticulturist, Hood River Br. Exp. Station, Hood River
C. G. BROWN, B.S........._
W. S. Ilsows, A,B., M.S....................... ...... ........................Horticulturist in Chsrge
Assistant Chemist
B. F. IIULLIS, U.S
A. S. Uijsiiitii, M.S.................................................................. 'ssistant in Farm Management
LEROY CiiiLos, A.B...__.............. ........Supt. Hood River Itranch Exp. Station, Hood River
Bacteriologist
G. V. CarsoN, M.S........_............................
H. K. Dv.Aa, B.S.............................
...Supt. Umatilla Branch Exp. Station Hermiston
Assistant 'Ieterinarian
F. M. EtiwAatis, B.S.................Asst. Animal Husbandman. East Ore. Br. Exp. Sta., Union
A. F. ENGRUF.Taots, U.S.................
......Supt. John Jacob Astor Br. Exp. Station, Astoma
L. N. Goopino, BA., U.S.........Jr. Plant Pathologist, U. S. Dept. of Agri.
W. V. HALVEILSEN, Ph.D.......
.............. ............. ........... ........Associate Bacteriologist
H. HARTMAN, M.S
dissociate Horticulturist (Pomology
E. Nb. HARVEY, Pli.D..........,..................._...
.... .........Horticulturiat (Physiology
BERTHA C. HIrE, B.A...Scientific Assistant Seed Lab., U. S. Dept. of Ari. (Seed Analyst)
K. F. HUTCIIINON, U.S
Asat. to Supt. of Harney Valley Branch hxp. Station, Burns
......
G. K, Hyst.op, B. S..........
Agronomist
W. 1. JOHNSON, J).V.M
Poultty Pathologist
It. JONES, Ph.D
Associate Dairy Husbandman
Chemist
S. JONES, M.S
....Agricultura I Engineer
G. W. KASLE, M.S
F. L. KNOWLTON, B.S
Poultry U usbandman
A. G. LUNN, B.S
Poultry Hushanilivan in Charge
M. 11. MCKAY, M.S
Plant Pathologist
H. G. MILLER, Ph.D
Chemist
G. A. MITCHELL, u.S
Asst. to Supt. of Sherman County Branch Exp. Station. Morn
DON C. MOTE, M.S
Entomologist
0. M. NELSON, B.S
Animal Husbandman
it. K. NoRRIS, B.S
Assistant to Supt. of Southern Oregon Branch Exp. Station, Talent
V. OLIVER, B S
Assistant Animal Husbandman
E. L. POTTER, M.S
Animal Husbandman
...
\V. L. Powts, M.S
.......
.........ChieI, Department of Soils
F. C. Rnsttii, M.S.................._....................Supl. Southern Oregon Br. Exp. Station, Talent
K. H. RottiNsog, A.B., M.S.................................................................._.......
Chemist
C. C. RtrTii, M.S............
......... ............Associote Agronomist
..... ...........
C. V. RUZEX, B.S......
Associate in Soils (Fertility)
H. A. Scuorit, M.S.....Asst. Agronomist, Forage Crops Investigation, U. S. Dept. of Agri.
C. E. SCUt7TER, M.S
....................Associate Horticulturist (Pomology)
H. I). SCUDiINR, u.S.
Chief in Farm Management
.._..........._.... .............
H. E. SELSY, U.S
.... ........Associate in Farm Management
0. SHATTUCK, M.S
Supt. Harney Valley Branch Exp. Station, Burns
J. N. SHAW, D.V.M
Assistant Veterinarian
J. E. SIMMoNs, M.S
.Assistant Bacteriologist
T. SIMMS, D.V.M
Veterinarian
D. E. STEPHENS,
Supt. Sherman County Br. Eap. Station, Moro
R. E. STEPHENSO N, Ph.1)._..................... ..
....Associate Soils Specialist
C. K. DON 11AM, D.V.M..............
B. G. THOMPSON,
E. F. TORGERSON,
E. H. \VIEGAND, U.S....
JOsEPH WILCOX, B.S..............__..
MAUD WILSON, B.S
RunT. WITHYCOMBE, B.S
W. W. YATES, B.S
S. M. ZEI.'LER, Ph.D
.Asisiant Entomologist
Assistant in Soils (Soil Survey)
Horticulturist (l-lorticultiiral Products)
..........................Assistanl in Entomology
Home Economist
Supt. Eastern Ore. Branch Exp. Station, Union
Assistant Chemist
Plant Pathologist
i.-.--..-.-----"---.-.---- _:.
SUMMARY
Most sprays, and combinations of two or more
spray materials, should be applied immediately after
they have been mixed in the tank.
If combination sprays are not mixed properly, the
chemical reactions may reduce the insecticidal or
fungicidal value as well as cause injury to foliage
and fruit.
The use of milk or casein spreader is advised with
many combinations to retard chemical changes.
This circular recommends methods of mixing var-
ious sprays and combinations of spray materials,
whereby injury from chemical reactions may be reduced to a minimum.
A table is given on pages 6- 7 showing procedure
for mixing sprays.
Sprays, Their Mixing and the Compatibility of Various Mixtures
By
R. H. ROBINSON
The successful production of orchard and certain other farm crops
depends to a large extent upon the control of insect pests and fungous
diseases that infest them. It is important, therefore, to know what
spray materials to use and how to prepare them to get best results.
When care is not exercised in the mixing of sprays, especially combinations of two or more materials, severe burning of the foliage and
fruit may occur. Another factor that may influence the quality of the
spray is the chemical reactions of combination sprays. The reaction
products may be far less toxic than the materials used, or they may be
soluble compounds that will burn the foliage and spot the fruit. The
use of hard water likewise may cause harmful results. These difficulties
may be avoided to a large extent if, first, some substance is added to the
sprays to reduce chemical reactions in the spray tank and, second, a
definite procedure is followed when mixing sprays in the tank for application.
In order that the difficulties attending the mixing of sprays may be
avoided and best results possible may be obtained, recommendations ar
made for the procedure that should be followed for preparing the different sprays. These recommendations are based mainly upon laboratory
studies of the chemical and physical reactions of the different combinations. The procedure that reduces the reaction to a minimum is advised.
MATERIALS USED TO REDUCE CHEMICAL REACTIONS IN COMBINATION SPRAYS
Investigations have shown that many substances may be used to
retard chemical reactions of various combination sprays. Among these
materials skim milk and commercial casein spreader have been found
most practicable. It may be explained that the commercial casein
spreader is prepared from skim milk. The casein in the milk is precipitated, dried, and mixed with three parts of hydrated lime. If, therefore,
hydrated lime is added to skim milk, an equally good spreader will be
obtained.
PROPORTIONS OF SKIM MILK OR CASEIN SPREADER
TO BE USED
Either skim milk or commercial casein spreader may be used in the
combination sprays to retard chemical reactions. When skim milk is
used, two quarts should be added for each 100 gallons of spray. About
i pound o hydrated lime (or pound quick-lime, well slaked) must be
added to each gallon of milk before it is used. Other milk products,
such as dried skim milk or sour milk may also be used. Lime also must
be added to these materials before using.
I
Procedure and Time to Add Various Spray Materials or Combinations of Spray Materials to the Spray Tank
Spray materials and
combinations
When tank is
full
When tank is
full
Lead arsenate
p
Iii orchard just before begin-
fling to spray
Add lead arsenate
k
Lime-sulfur, liquid or dry,
self-boiled lime-sulfur,
Oregon cold-mix lime-sulfur
Id
Id
Add any tune
or other sulfur spray
Bordeauxprepare home-made
mixture
I')
Add required amount of slaked
quick-lime or hydrated lime
sprays.
ration.
z
at Q-iull mark
Add litne.sulfur or other sulfur
sprays
Add milk + lime or casein spreader
'-5
C
Dilute oil with equal amount of water mix well, and add slowly to spray tank
Add lead arsenate
Id
Id
00
Combination
Lead arsenate and
sulfur sprays and
nicotine sulfate
Spray immediately after prepa-
followed by nicotine sulfate.
Miscible oils or
"cnld prepared' oil emulsions
Lead arsenate and
lime-sulfur or other sulfur
per sulfate solution.
Add milk + lime or casein spreader
Nicotine sulfate
Combination
Start agitator and run in diluted cop-
Add nicotine sulfate
Add milk + lime or casein spreadtr
followed by lime-sulfur or other sulfur spray.
Add lead arsenate
Combination
Lead arsenate and
nicotine sulfate
Add nicotine sulfate
Add milk + lime or casein spreader
Add lead arsenate
Add nicotine sulfate
Add milk + lime or casein spreader
Add lime-sulfur slowly just before tank is full
Combination
Nicotine sulfate and
lime-sulfur or any other
sulfur spray
Combination
Bordeaux (home-made) and
oil emulsions
Add required amount of slaked
quick-lime or good hydrated
oil, mixed with equal volAdd very dilute copper sulfate solu-Add
ume of water just before tank
Add required amount of slaked
quick-lime or good hydrated
Add very dilute copper sulfate solu-Add lead arsenate just before
lime
tion
J-)
U)
is full.
H
Combination
Bordeaux (home-made) and
lead arsenate
lime
Combination
Add lead arsenate followed by oil emulsion just before tank is full
Oil emulsion and
lead arsenate
Combination
Bordeaux (home-made) and
nicotine sulfate
Combination
Bordeaux (home-made) and
nicotine sulfate and
lead arsenate
Combination
Bordeaux and
beginning to spray.
tion
Add required amount of slaked
quick-lime or good hydrated
lime
tion
Add nicotine sulfate mixed with
a gallon of water.
()
C
Add required amount of slaked
quick-lime or good hydrated
lime
Add very dilute copper sulfate solu-
Add very dilute copper sulfate solution followed by nicotine sulfate
mixed with a gallon of water
Add lead arsenate just before
beginning to spray.
B
I-'
This combination SHOULD NOT BE USED
"1
lime-sulfur
Notes and explanations
Milk + lime" means
pound lime (hydrated lime or quick-lime, well slaked) mixed in 2 quarts skim milk for each 100 gallons of
spray.
Casern spreader' refers to any of the commercial casen spreadersto be used at the rate of pound to 100 gallons of spray.
Copper sulfate" is often called "bluestone" or blue vitriol."
Nicottne sulfate' is the comn ercial 'Black Leaf 40," "Hall 40% Nicotine," or other brands.
".l
8
0. A. C. EXPERIMENT STATION CIRCULAR 68
If the orchardist desires to use commercial casein spreader instead
pound to each 100 gallons of spray should be added. This
amount is not recommended for spreading purposes, but to retard chemical action in certain combination sprays.
of skim milk,
CASEIN SPREADER OR SKIM MILK FOR SPREADING
PURPOSES
The Experiment Station has not given any definite recommendations regarding the use of casein spreader for spreading purposes only.
Many factors influence its practicability. The orchardist is best able
perhaps to know whether, under his particular conditions, it is advisable
to go to the added expense of using spreader. The cost, severity of
disease or insect infestation, spray used, time sprayed, climatic conditions, and other factors must be considered. If the orchardist finds it
desirable to use the casein for spreading purposes, the skim milk should
be used if available. This substitute will reduce costs more than a half
and be equally effective.
When used for spreading purposes a larger amount of skim milk or
casein spreader should be added than is recommended to retard chemical
action in combination sprays. Three quarts of skim milk or pound of
the commercial casein spreader to each 100 gallons of spray is sufficient
for most sprays. As noted above, pound of hydrated lime should be
added to each gallon of milk used. If sweet skim milk is not available
sour milk may be used.
MIXING OF ONE SPRAY ONLY
When one spray material only is to be used the principal precaution to take is to apply the spray immediately after mixing a tank full
and not let it stand before using. If the orchardist desires to use milk
or the commercial casein as a spreader it should be added after the tank
is about three-fourths filled with water. This is advisable on account of
the excess foaming that occurs if the spreader is added sooner. The
time for adding the various materials and precautions that should be
taken are given under the following heads.
Lead arsenate. When lead arsenate is used alone it may be added
to the spray tank at any time during the filling process. Since it is very
important, however, to add the lead arsenate last in combination sprays,
it may be set down as a general rule that "lead arsenate should be added to
the tank in the orchard just before starting to spray." By following this
procedure the time for solubility and chemical reaction is diminished
to a minimum.
Lime-sulfur (liquid or dry); Oregon cold mix; self-boiled lime.sulfur;
other sulfur sprays. These spray materials may be added to the tank
any time during the filling process.
Bordeaux mixture. The home prepared product only is advised
since the commercial paste or powder bordeaux mixture will not adhere
sufficiently long to give as satisfactory results as the home-made material.
Methods and precautions for the preparation of home-made bordeaux
are given in Oregon Experiment Station Bulletin 201.
SPRAYSTHEIR MIXING AND COMPATIBILITY
9
To mix bordeaux for immediate application the required amount of
slaked quick-lime (or fresh hydrated lime) is added before the tank is
half full. After the water reaches about the three-fourths full mark, the
dilute copper sulfate is added slowly with the agitator going. This
spray should be applied immediately, since it soon begins to change
to the crystalline form which will not adhere well.
If it is necessary to let a tank of spray stand around, even for two
hours, a little sugar should be added to prevent changing to the crystalline state. About one ounce of sugar to 100 gallons will suffice. This
should be dissolved in a little water and added with the lime, although
fair results will be obtained even if added after the mixture is made.
Nicotine sulfate. The effectiveness of nicotine sprays depends in a
large measure upon contact with the insect and subsequent volatility.
It is important, therefore, to use milk or casein spreader with this spray.
This treatment will increase contact by wetting and the lime present will
increase the volatility of the nicotine.
To prepare this spray proceed as follows: The tank is first filled
about three-fourths full and the skim milk or commercial spreader is
added. An extra pound of good hydrated lime or slaked quick-lime is
then added. The required amount of nicotine is diluted with a gallon
or more of water and then added to the spray tank.
Soap may be used advantageously in nicotine sprays for spreading
purposes on garden crops, hops, and for certain other plants, but the
milk or casein spreader only should be used for orchard work. If soap
is used in orchard spraying any time after the buds open, severe injury
may occur, especially if sprayed with lead arsenate.
Oil emulsion and miscible oils. All types of oil sprays should be
diluted with an equal amount of water and well mixed before adding to
the spray tank. This reduces a tendency of the oil to separate out.
The tank is filled with water, about three-fourths full, and the diluted
oil spray added. The agitator should be going as the oil is slowly
poured into the tank. It is best to apply immediately after a tank full
has been mixed, as the oil may have a tendency to rise to the surface
and separate out.
COMBINATION SPRAYS
It is in the combination sprays that more than ordinary care should
be exercised during the mixing process. Procedures are given below for
most combinations that may be used in Oregon. The table given on
pages 6-7 should be studied, and the order of adding the various materials
to the spray tank should be followed carefully. Where milk or casein
spreader is advised, it is for the purpose of retarding chemical action
and not for spreading effects.
Lime-sulfur (or other sulfur spray)lead arsenate. In all combination sprays where lead arsenate is one of the materials used, milk or
casein spreader should be added to retard chemical action. When the
tank is three-fourths full the lime-sulfur or other sulfur spray may be
added, followed by the milk or casein spreader. Immediately before
starting operation in the orchard, the lead arsenate is sifted into the
tank.
0. A. C:. EXPERIMENT STATION CIRCULAR 68
10
A tank of this combination should be sprayed as soon as the lead
arsenate is added. Although the milk or casein spreader retards the
chemical action, enough may occur in several hours to diminish somewhat the toxicity of the combination and to cause burning of foliage.
Nicotine sulfatelead arsenate. As previously stated, it is important
to use milk or casein spreader with all sprays containing nicotine. The
addition of an extra pound of lime per 100 gallons also is well worth
while.
To mix this combination the nicotine sulfate is added to the tank
any time before the water reaches the three-fourths full mark. The milk
and an extra pound of lime are then added. Finally just before starting
to spray, the lead arsenate is sifted into the tank.
Nicotine sulfatelime-sulfurlead arsenate. This three-spray combination is often used in Oregon, and for best results the order of adding
these materials should be followed closely. When the water reaches
the three-fourths full mark the nicotine sulfate is first added, followed
by the milk and lime or casein spreader. The agitator is then started
and the lime-sulfur is slowly poured in. Finally, just before starting to
spray, the lead arsenate is added.
It is important to follow the above procedure in order to disperse
the nicotine sulfate uniformly throughout the mixture. If, for example,
the nicotine is added to the lime-sulfur, a stringy coagulated mass of
precipitated nicotine is formed which cannot be dispersed by the movement of the agitator.
Nicotine sulfatelime-sulfur. The same procedure should be followed
for this combination as for the nicotine sulfatelime-sulfurlead arsenate
mixtures, except that the lead arsenate is not added. Other precautions
regarding the use of milk or casein spreader and the addition of an extra
pound of lime should be taken.
Bordeaux mixture--lead arsenate. The bordeaux mixture should be
prepared as described previously under 'bordeaux mixture," pages 8-9.
The lead arsenate is then added just before beginning to spray.
Oil emulsionlead arsenate. It is perhaps advisable in this combination to make an exception to the general rule "to add the lead arsenate
last." On account of the consistency of the oil emulsion it is difficult to
disperse quickly and uniformly the lead arsenate throughout the mixture.
If, therefore, the lead arsenate is added when the tank is about threefourths full and then followed by the oil emulsion an excellent, uniform
mixture will be obtained.
As stated above, the oil emulsion should be diluted with an equal
amount of water before pouring slowly into the tank. This combination
spray should be applied immediately after it has been mixed.
Bordeauxoil emulsion. The bordeaux should be prepared as de-
scribed previously under "bordeaux mixture," pages 8-9. After the tank
is nearly filled with the bordeaux, the oil emulsion is slowly added. As
noted above, the oil emulsion should be mixed thoroughly with an equal
amount of water before adding to the tank.
SPRAYSTHEIR MIXING AND COMPATIBILITY
11
Bordeauxnicotine sulfate. The bordeaux should be prepared carefully as described under "bordeaux mixture," pages 8-9. The required
amount of nicotine sulfate is diluted with about a gallon of water and
added just before leaving the filling station.
Bordeauxnicotine sulfatelead arsenate. This combination should
be prepared as outlined under "bordeauxnicotine sulfate" in the previous
paragraph and the lead arsenate added in the orchard just before beginning to spray.
Bordeauxlime-sulfur. This combination should not be used. The
chemical reaction between the two spray materials is so complete that
the individuality of both is destroyed. It is questionable whether the
reaction products of the combination have any fungicidal or insecticidal
value.